This project strives ultimately to eliminate 90% of the deaths and injuries caused by trucks and buses colliding with cars and pedestrians. Trucks & buses average one collision per year in the US. Over 400,000 of these result in injuries and 4,000 in deaths. Ninety percent of the Liability insurance cost for trucks and buses is for the people they kill or injure in collisions, roughly $12 billion per year. When used, the Liwon bumper bag is designed to eliminate 90% of collision deaths & injuries. The Liwon bumper airbag should pay for itself many times over every time it is used. Trucks inflate the bumper airbag before hitting a smaller vehicle. The driver hits a switch to inflate the airbag or a collision radar system inflates it. In most accidents, the operator has hit the brakes anyway and an extra push could trigger the airbag. The bumper bag is an extra tool when brakes are not enough. The specific objective of this Phase I research and development effort is to design an optimum bumper airbag system. For the first milestone, we will use a sophisticated, computerized, mathematical Finite Element Model of the complete bumper airbag system to accurately simulate 1) collisions with cars and pedestrians, 2) inflation of the airbag and inflator concepts, and 3) crosswinds and headwinds during and after airbag inflation. We will vary key design input variables by plus and minus say 20% to see their effect on performance variables. Input variables will include airbag length, front face slant angle, inflator pressure flow rate profile, and others. Performance variables will include inflation time, bumper-to-bumper contact speed, aerodynamic lift force, cost, etc. For the second milestone, we will use these accurate simulations to make simple equations of the bumper airbag system behavior using the key design and performance variables. We will use these simple equations in an Optimization program to develop the best design for the bumper airbag system. In Phase II, we will use this design to build a working prototype.